OTHER ANSWERS

According to the Google support articles that I found on this issue, it appears that you may need to check settings or re-embed the calendar. I also saw another support article that hinted at the time zone being an issue. If the calendars are not on the same timezone, it won't update at the same time.

Note that this is a Google Calendar issue, so we do not have direct access to Google's code to determine what may be causing the issue. You may need to consult Google's support pages in order to find further assistance if you require it.

If you have any further questions, please contact technical support or leave a comment at the bottom of the page.